Nozzle of the ladle for steel casting



R. GODAI NOZZLE 0F THE LADLE FOR STEEL CASTING Filed Feb. 14, 1923 Big. 1

Imwfor R. G-adcul Patented Dec. 30, 1924.

UNITED STAT nYosAKU sonar, or TOKYQ, .zmrnn.

NOZZLE OF THE 'LADLE FOR STEEL CASTENG.

Application filed February 14, 1928. Serial No. 618,982.

exact description of the invention, such as V will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to ladles, and it particularly consists of improvements in a nozzle'pro-vided in the ladle bottom.

This invention has a particular application in reducing the velocity of molten steel when flowing out through the nozzle, its application not being necessarily limited to steel casting.

For the purpose of adjusting the flow of molten steel running out of the ladle nozzle, several devices heretofore have been disclosed and practically applied to steel casting. But these are not satisfactory.

This invention has for its object to provide a very simple and effective means in reducing the velocity of molten steel flowing out through the nozzle passage of the ladle.

In carrying this invention into effect, an annular groove is formed on the nozzle passage in the ladle, whereby the molten steel will run out with a desired reduced velocity when it is discharged from an orifice or lower end of the nozzle.

For a better understanding of this invention, the accompanying drawings are referred to, where an embodiment of this invention is shown for the purpose of er:- plaining the principles thereof. In the accompanying drawings, Fig. 1 is a vertical sectional view of a ladle which is provided with a nozzle formed in accordance with this invention and associated with its stopper; Fig. 2 is a fragmentary sectional view, in an enlarged scale, of the nozzle and an end port-ion of the stopper.

Similar references indicate same or similar parts throughout the figures in the accompanying drawings.

Referring to the drawings, the ladle has its body A lined with a suitable refractory material B and at the bottom of the ladle there is provided a nozzle G the passage of which will be controlled by means of a stopper D.

According to this invention, an annular groove E, the bottom of which is preferably rounded as shown,'is formed on the interior surface of the nozzle passage 33, in such a way that the center line YY of the nozzle passage F is perpendicular to a plane in which the annular groove E is laid, and that the said center line passes through the center point of the annular groove The diameter of the annular groove E is made larger than that of the nozzle passage F, so that the nozzle passage which is proper to be strait and to have an uniform cross section is expanded by the annular groove E as shown. The annular groove E is preferably formed in such a position that when the stopper 1) is raised from its seat at the top end of the nozzle'G, the molten steel flowing out through the space G, opened between the stopper and its seat, may run straitly on toward, the annular groove E, as shown with arrow heads. The annular groove E is formed on the upper part of the inside of the nozzle and practically a little below the theoretical level as shown at E, since the molten metal after intersecting at the point H is deflected downward, the amount of deflection being dependent upon the velocity of the flowing molten metal which is due to the height of the molten metal in the ladle.

The operation of the ladle provided with a nozzle as thus constructed and arranged according to this invention is as follows The laddle A is filled at first with molten steel as usual after the nozzle passage F has been closed by means of the stopper D. l/Vhen it is desired to pour the molten steel into the mould the stopper D is raised so that a conical space G is opened around the lower end of the stopper D and between the said end and the seat. Then the moulten steel in the ladle runs out through the conical space G now opened with a Velocity due to the height of the molten steel in the ladle, neglecting the throttling effect caused by the stopper D, and also the skin friction of the stopper and its seat. The molten steel passing through the said conical space G will naturally form a conical. meeting at a point H on the center line YY of the nozzle passage F, the point H being a vertex of an i'nversed cone enclosed by the molten steel.

A portion of the molten steel, which has met in the said point H, will vertically flow down along the center line of the nozzle passage, with somewhat reduced velocity.

i is greatly reduced.

The remaining portion of the molten steel will cross itself at the said point H, then it will rush forward and strike the annular groove E, whereby it is reflected in an op posite direction. Then the molten steel thus reflected will meet again, itself and with the said other portion of the molten steel which is vertically flowing down through the central part of the nozzle passage F, thus the velocity of the flow of molten steel If the reflected molten steel has still enough kinetic energy left in r it to rush forward and strike theo-pposite surface of the nozzle passage-F, it may be reflected again and combine with the col umn of molten steel flowing downvertically whereby resulting in the further reduction 7 of the velocity of the flow of molten steel.

If the single annular groove is found insufiicientin certain cases, one or more an-v nular grooves are added conveniently, and such added grooves have the similar effect of still reducing the velocity of themolten steel for the same reason as the single one has, as. explained above, the kinetic energy amaze of the flowing molten steel being absorbed" by its battering action. against the "annular grooves and alsoagainst itself and we can obtain as slow as we please of the flow vof the molten metal when it comes out from the nozzle at its lowest end which is of the paramount importance in all steel industries.

What I claim as new and desire to secure by Letters Patent of the United States, is

2. A ladle nozzle provided with "an annw lar groove, the bottom of which is preferably ronnded, whereby the velocity of molten steel is reduced.

Dated at Tokyo, Japan," this17th day or January 1923. I i V In testimony whereof I affix my signature; RYOSAKU GODAL. V 

